This invention relates generally to cooking vessels or containers and particularly to cooking vessels for commercial use, such as in restaurants and the like. The invention is specifically concerned with a pasta cooker in which the cooked product coacts with boiling water to develop a foam. The foam (as well as the agitation of the water due to boiling) often causes a conventional water level sensor to sense that the water level in the cooking vessel is higher than it really is.
The prior art discloses devices for "isolating" the water by use of a water level tube. The tube is external to the container and communicates with the container below the normal water level. Thus, the sensors in the water level tube are not subjected to the foaming and bubbling of the water that occurs in the container. The system of the invention utilizes a sensor tube that is coupled to the lower portion of the cooking vessel and isolated from the surface activity during boiling of foodstuffs, but is angled away from the container to form a substantially straight through passageway for enabling easy and thorough cleaning of the tube and container. In contrast to the prior art, there is a gradual radius at the bottom of the sensor tube where it communicates with the container. Such a bend is simple to negotiate with conventional cleaning equipment, unlike the angular bends of the prior art devices. Prior art sensor tubes that are positioned inside the container pose similar cleaning problems as well as taking up valuable cooking space.
The invention also includes an automatic control system for controlling the water temperature in the container. In particular, a pair of temperature sensors communicate with the water in the container with each sensor being coupled to a respective thermostat which, in turn, controls a respective energy flow device. In the gas version, the energy flow devices comprise gas valves and in the electric version, the energy flow devices comprise electrical relays. The energy flow devices supply energy to their respective heating units and are connected in series with the energy source. With the arrangement, one of the energy flow devices is cycled on and off in response to its thermostat and sensor when the temperature of the water is near boiling whereas the other energy flow device is cycled on and off by its associated thermostat and sensor at the boiling temperature of water. The precise settings of the thermostats may be adjusted in accordance with preferences of the cook. The inventive system enables very rapid heating of the water in the container by activating both heating units simultaneously as well as close control of the temperature rise in the container by turning one of the heating units off as the water in the vessel approaches the boiling temperature.